THE METHODIC SECT, which was founded by the Roman physician Themison,[38] a disciple of Asclepiades, as they conceived all diseases to depend upon _overbracing_, or on _relaxation_, so did they class all medicines under the head of _relaxing_ and _bracing_ remedies; and although this theory has been long since banished from the schools, yet it continues at this day to exert a secret influence on medical practice, and to preserve from neglect some unimportant medicines. The general belief in the relaxing effect of the _warm_, and the equally strengthening influence of the _cold_ bath, may be traced to conclusions deduced from the operations of hot and cold water upon parchment and other inert bodies.[39] THE STAHLIANS, under the impression of their ideal system, introduced _Archœal_ remedies, and many of a superstitious and inert kind; whilst, as they on all occasions trusted to the constant attention and wisdom of nature, so did they zealously oppose the use of some of the most efficacious instruments of art, as the Peruvian _bark_; and few physicians were so reserved in the use of general remedies, as bleeding, vomiting, and the like; their practice was therefore imbecile, and it has been aptly enough denominated, “_a meditation upon death_.” They were however vigilant in observation and acute in discernment, and we are indebted to them for some faithful and minute descriptions. THE MECHANICAL THEORY, which recognised “_lentor and morbid viscidity of the blood_,” as the principal cause of all diseases, introduced attenuant and diluent medicines, or substances endued with some mechanical force; thus Fourcroy explained the operation of mercury by its specific gravity,[40] and the advocates of this doctrine favoured the general introduction of the preparations of iron, especially in schirrus of the spleen or liver, upon the same hypothetical principle; for, say they, whatever is most forcible in removing the obstruction, must be the most proper instrument of cure; such is _Steel_, which, besides the attenuating power with which it is furnished, has still a greater force in this case from the _gravity_ of its particles, which, being seven times specifically heavier than any vegetable, acts in proportion with a stronger impulse, and therefore is a more powerful deobstruent. This may be taken as a specimen of the style in which these mechanical physicians reasoned and practised.